Multi-User Medical Robotic System for Collaboration or Training in Minimally Invasive Surgical Procedures

ABSTRACT

A multi-user medical robotic system for collaboration or training in minimally invasive surgical procedures includes first and second master input devices, a first slave robotic mechanism, and at least one processor configured to generate a first slave command for the first slave robotic mechanism by switchably using one or both of a first command indicative of manipulation of the first master input device by a first user and a second command indicative of manipulation of the second master input device by a second user. To facilitate the collaboration or training, both first and second users communicate with each other through an audio system and see the minimally invasive surgery site on first and second displays respectively viewable by the first and second users.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 15/607,676, filed May 29, 2017, which is a continuation of U.S. patent application Ser. No. 15/006,555, filed Jan. 26, 2016, now U.S. Pat. No. 9,666,101, which is a divisional of U.S. patent application Ser. No. 13/965,581, filed Aug. 13, 2013, now U.S. Pat. No. 9,271,798, which is a divisional of U.S. patent application Ser. No. 11/319,012, filed Dec. 27, 2005, now U.S. Pat. No. 8,527,094, which claims priority from U.S. Provisional Application No. 60/725,770, filed Oct. 12, 2005, each of which is incorporated herein by this reference.

U.S. patent application Ser. No. 11/319,012 is also a continuation-in-part of U.S. patent application Ser. No. 11/025,766, filed Dec. 28, 2004, now abandoned, which is a continuation of U.S. patent application Ser. No. 10/214,286, filed Aug. 6, 2002, now U.S. Pat. No. 6,858,003, which is a divisional of U.S. patent application Ser. No. 09/436,982, filed Nov. 9, 1999, now U.S. Pat. No. 6,468,265, which claims priority from U.S. Provisional Patent Application No. 60/109,359, filed Nov. 20, 1998, U.S. Provisional Application No. 60/109,301, filed Nov. 20, 1998, U.S. Provisional Application No. 60/109,303, filed Nov. 20, 1998, and U.S. Provisional Application No. 60/150,145, filed Aug. 20, 1999, and which is a continuation-in-part of U.S. patent application Ser. No. 09/433,120, filed Nov. 3, 1999, now U.S. Pat. No. 6,659,939, which is a continuation-in-part of U.S. patent application Ser. No. 09/399,457, filed Sep. 17, 1999, now abandoned, which is a continuation-in-part of U.S. patent application Ser. No. 09/374,643, filed Aug. 16, 1999, now abandoned, which claims priority from U.S. Provisional Patent Application No. 60/116,891, filed Jan. 22, 1999, U.S. Provisional Patent Application No. 60/116,842, filed Jan. 22, 1999, and U.S. Provisional Patent Application No. 60/109,359, filed Nov. 20, 1998, each of which is incorporated herein by this reference.

U.S. patent application Ser. No. 11/319,012 is also a continuation-in-part application of U.S. patent application Ser. No. 10/948,853, filed Sep. 23, 2004, now U.S. Pat. No. 7,413,565, which is a divisional of U.S. patent application Ser. No. 10/246,236, filed Sep. 17, 2002, now U.S. Pat. No. 6,951,535, which is a continuation of U.S. patent application Ser. No. 10/051,796, filed Jan. 16, 2002, now U.S. Pat. No. 6,852,107, each of which is incorporated herein by this reference.

FIELD OF THE INVENTION

The present invention generally relates to minimally invasive robotic surgery systems and in particular, to a multi-user medical robotic system for collaboration or training in minimally invasive surgical procedures.

BACKGROUND

While clinical growth of laparoscopic procedures has stalled, tele-operated robotic surgical systems have been successful in achieving greater procedure development and clinical acceptance in several surgical fields. Two examples of such surgical robotic systems include the da Vinci® Surgical System of Intuitive Surgical, Inc., Sunnyvale, Calif., and the Aesop® and Zeus® robot systems of Computer Motion, Inc., which has been acquired by Intuitive Surgical, Inc.

For example, the da Vinci® surgical system can be used for a wide variety of surgical procedures such as mitral valve repair, Nissen Fundoplication for the treatment of GERD disease, gastric bypass surgery for obesity, radical prostatectomy (da Vinci® Prostatectomy) for the removal of the prostate, esophageal surgery, thymectomy for myasthenia gravis, and epicardial pacemaker leads for biVentricular resynchronization.

Minimally invasive surgery offers many benefits over traditional open surgery techniques, including less pain, shorter hospital stays, quicker return to normal activities, minimal scarring, reduced recovery time, and less injury to tissue. Consequently, demand for minimally invasive surgery is strong and growing.

Since robotic minimally invasive surgery (“RMIS”) is still a nascent field, however, there are no commercially available training systems that allow a trainee and mentor to experience the same environment, and physically interact as they would in open or even conventional laparoscopic surgery training. Instead, current RMIS training consists of training courses explaining the robotic device and surgical technique accompanied by laboratory practice in animal and cadaver models, followed by watching already proficient surgeons perform the procedure. A proficient surgeon then assists/supervises the newly trained surgeon during his or her initial procedures.

In a tele-robotic paradigm, this mentoring problem can be generalized irrespective of the location of the two surgeons. However, when they are collocated, the ability to view the surgical scene together, combined with the ability to exchange or share control of the instruments can enable physical interaction between the trainee and the mentor, and provide a superior training environment.

BRIEF SUMMARY

Thus, a multi-user medical robotic system which allows a mentor surgeon to communicate with trainee surgeons, to see the same surgical site as the trainee surgeons, to share control of robotically controlled surgical instruments with the trainee surgeons so that they may feel through their controls what the mentor surgeon is doing with his/hers, and to switch control to selected ones of the trainee surgeons and over-ride that control if necessary during the performance of a minimally invasive surgical procedure, would be highly beneficial for training purposes.

In addition, such a multi-user medical robotic system would also be useful for collaborative surgery in which multiple surgeons work together as a team (i.e., in collaboration) to perform a minimally invasive surgical procedure.

Accordingly, one object of the present invention is to provide a multi-user medical robotic system that facilitates collaboration between surgeons while performing minimally invasive surgical procedures.

Another object is to provide a multi-user medical robotic system that facilitates training of surgeons to perform minimally invasive surgical procedures.

These and additional objects are accomplished by the various aspects of the present invention, wherein the embodiments of the invention are summarized by the claims below.

Additional objects, features and advantages of the various aspects of the present invention will become apparent from the following description of its preferred embodiment, which description should be taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a top view of a multi-user medical robotic system for collaboration or training in minimally invasive surgical procedures, utilizing aspects of the present invention.

FIGS. 2-3 illustrate simplified front views respectively of mentor and trainee master control stations configured to utilize aspects of the present invention.

FIG. 4 illustrates a block diagram of a master/slave control system included in the multi-user medical robotic system, utilizing aspects of the present invention.

FIGS. 5-9 illustrate block diagrams of selected master/slave associations for a multi-user medical robotic system, utilizing aspects of the present invention.

FIG. 10 illustrates a block diagram of components of the multi-user medical robotic system for selective association of masters and slaves, utilizing aspects of the present invention.

FIG. 11 illustrates an example of input/output ports for an association module, utilizing aspects of the present invention.

FIGS. 12 and 13 illustrate routing tables corresponding to the master/slave associations of FIGS. 9 and 8, respectively, of an association module utilizing aspects of the present invention.

FIGS. 14 and 15 illustrate block diagrams for alternative embodiments of a shared command filter of an association module, utilizing aspects of the present invention.

FIGS. 16 and 17 schematically illustrate alternative robotic telesurgical systems utilizing aspects of the present invention.

DETAILED DESCRIPTION

FIG. 1 illustrates, as an example, a multi-user medical robotic system 100 useful for collaboration or training in minimally invasive surgical procedures. For example, in a collaborative operation, a team of two or more proficient surgeons may work together to perform a minimally invasive surgical procedure, or an expert surgeon may advise a primary surgeon performing a minimally invasive surgical procedure. In a hands-on training environment, a mentor surgeon may act as a mentor or teacher to train one or more trainee surgeons in minimally invasive surgical procedures.

Although configured in this example for a local environment with all participants locally present, the multi-user medical robotic system 100 may also be configured through a network connection for remote participation by one or more participants. For example, a remote surgeon may provide guidance or support to a primary surgeon at a local operating site. In such case, the advising surgeon may share the immersive audio/video environment with the primary surgeon, and may access the surgical instruments as desired by the primary surgeon.

Although a training example is described herein, the described components and features of the system 100 are also useful in collaborative surgery. In particular, it is useful for a lead surgeon in the case of a collaborative procedure to control the selective association of certain surgical tools and/or an endoscope with any one of the participating surgeons during a minimally invasive surgical procedure, just as it is for a mentor surgeon in the case of a training session to control the selective association of certain surgical tools and/or an endoscope with any one of the trainee surgeons during a minimally invasive surgical training session. Also, it is useful in both the collaboration and training environments for all participants to be able to view the surgical site and to communicate with each other during the surgical procedure or training session.

In reference to FIG. 1, a Mentor Surgeon (M) instructs or mentors one or more Trainee Surgeons, such as (T1) and (TK), in minimally invasive surgical procedures performed on a real-life or dummy Patient (P). To assist in the surgical procedures, one or more Assistant Surgeons (A) positioned at the Patient (P) site may also participate.

The system 100 includes a mentor master control station 101 operative by the Mentor Surgeon (M), a slave cart 120 having a plurality of slave robotic mechanisms (also referred to as “robotic arm assemblies” and “slave manipulators”) 121-123, and one or more trainee master control stations, such as trainee master control stations 131 and 161, operative by Trainee Surgeons, such as Trainee Surgeons (T1) and (TK). The mentor master control station 101, in this example, communicates directly with the slave cart 120, and the trainee master control stations communicate indirectly with the slave cart 120 through the mentor master control station 101.

The slave cart 120 is positioned alongside the Patient (P) so that surgery-related devices (such as 157) included at distal ends of the slave robotic mechanisms 121-123 may be inserted through incisions (such as incision 156) in the Patient (P), and manipulated by one or more of the participating surgeons at their respective master control stations to perform a minimally invasive surgical procedure on the Patient (P). Each of the slave robotic mechanisms 121-123 preferably includes linkages that are coupled together and manipulated through motor controlled joints in a conventional manner.

Although only one slave cart 120 is shown being used in this example, additional slave carts may be used as needed. Also, although three slave robotic mechanisms 121-123 are shown on the cart 120, more or less slave robotic mechanisms may be used per slave cart as needed.

A stereoscopic endoscope is commonly one of the surgery-related devices included at the distal end of one of the slave robotic mechanisms. Others of the surgery-related devices may be various tools with manipulatable end effectors for performing the minimally invasive surgical procedures, such as clamps, graspers, scissors, staplers, and needle holders.

Use of the stereoscopic endoscope allows the generation and display of real-time, three-dimensional images of the surgical site. Although the stereoscopic endoscope is preferred for this reason, a monoscopic endoscope may alternatively be used where either three-dimensional images are not needed or it is desirable to reduce communication bandwidth requirements.

Alternatively, the system may include multiple endoscopes providing each individual surgeon with a desired view of the workspace. Advantageously, the multiple endoscopes may even be packaged in a single instrument, but with separate steerable camera tips. Optionally, these multiple endoscopes may provide different fields of view such as using a very wide field of view (e.g. with a fish-eye lens) that is appropriately rectified before being displayed to the surgeon.

To facilitate collaboration between surgeons or training of trainee surgeons in minimally invasive surgical procedures, each of the participating surgeons has an associated display to view the surgical site, and a communication means such as a microphone and earphone set to communicate with other participating surgeons.

More particularly, a display 102 is provided with or integrated into the mentor master control station 101, a display 132 is provided with or integrated into the trainee master control station 131, and a display 142 is provided on a vision cart 141 which is in view of the one or more Assistant Surgeons (A), so that the Mentor Surgeon (M), the Trainee Surgeon (T), and the Assistant Surgeon(s) (A) may view the surgical site during minimally invasive surgical procedures.

The vision cart 141, in this example, includes stereo camera electronics which convert pairs of two-dimensional images received from the stereoscopic endoscope into information for corresponding three-dimensional images, displays one of the two-dimensional images on the display 142 of the vision cart 141, and transmits the information of the three-dimensional images over a stereo vision channel 111 to the master control stations of participating surgeons, such as the mentor master control station 101 and the trainee master control stations, for display on their respective displays. For displaying stereo information using properly configured conventional displays, the vision cart 141 may contain devices for frame synchronization, and in that case, conventional video cables may be sufficient for sharing this information between collocated surgeons.

The communication means provided to each of the participants may include individual microphone and earphones (or speaker) components, or alternatively, individual headphone sets, such as headphone set 103 shown as being placed on the head of the Mentor Surgeon (M), as part of a conventional audio system. Preferably a duplex audio communication system (microphone and speaker pair) is built into each surgeon's master control station. Alternatively, headsets may be used, including those using wireless communications to provide maximum comfort and freedom of movement to their users or those that may be connected through wires to their respective master control stations or slave cart, which are in turn, are connected together through mentor/slave lines 110 and mentor/trainee lines 112 for voice communications between the Mentor, Trainee and Assistant Surgeons.

In addition to transmitting voice communications, the mentor/slave and the mentor/trainee lines, 110 and 112, also transmit data. For high bandwidth and low latency communication, the lines 110 and 112, as well as the stereo vision channel lines 111, are preferably composed of fiber optic communication cables/channels, which are especially useful when any of the mentor master control station 101, the trainee master control stations (such as 131 and 161), and the slave cart 120 are remotely situated from the others. On the other hand, for co-located surgeons, normal shielded video and audio cables may be sufficient, while fiber optical communication channels may be used for the mentor/slave or mentor/trainee data transfer lines.

FIGS. 2-3 illustrate simplified front views of the mentor master control station 101 and the trainee master control station 131. The mentor master control station 101 includes right and left master input devices, 203 and 204, whose manipulations by the Mentor Surgeon (M) are sensed by sensors (not shown) and provided to an associated processor 220 via an instrumentation bus 210. Similarly, the trainee master control station 131 includes right and left master input devices, 303 and 304, whose manipulations by the Trainee Surgeon (T1) are sensed by sensors (not shown) and provided to an associated processor 320 via an instrumentation bus 310. Each of the master input devices (also referred to herein as “master manipulators”) may include, for example, any one or more of a variety of input devices such as joysticks, gloves, trigger-guns, hand-operated controllers, and the like.

The mentor master control station 101 is preferably configured with one or more switch mechanisms to allow the Mentor Surgeon (M) to selectively associate individual of the slave robotic mechanisms 121-123 with any of the master input devices of the mentor master control station 101 and the trainee master control stations. As one example, two switch mechanisms may be activated by right or left buttons, 205 and 207, positioned on the right and left master input devices, 203 and 204, so as to be manipulatable by right and left thumbs of the Mentor Surgeon (M).

As another example, two switch mechanisms may be activated by right or left footpedals, 215 and 217, which are positioned so as to be manipulatable by right and left feet of the Mentor Surgeon (M). One switch mechanism may also be voice activated by the Mentor Surgeon (M) using his headset 103 or another microphone (not shown), which is coupled to the processor 220 so that it may perform voice recognition and processing of the spoken instructions of the Mentor Surgeon (M).

For complex associations of various aspects of system master input devices and slave robotic mechanisms, a simple binary switch (or combinations of switches) may not be suitable. In such cases, a more flexible association selector may be required, such as a menu of available options displayed on the display 102 of the mentor master control station 101 that the Mentor Surgeon (M) may select from, by using a conventional pointing device, touch screen, or voice activation. The master input devices or input devices built into the master input devices may also be used for this purpose.

To perform a minimally invasive surgical procedure, the operating surgeons perform the procedure by manipulating their respective master input devices which in turn, causes associated slave robotic mechanisms to manipulate their respective surgery-related devices through minimally invasive incisions in the body of the Patient (P) while the surgeons view the surgical site through their respective displays.

The number of surgery-related devices used at one time and consequently, the number of slave robotic mechanisms in the system 100 will generally depend on the diagnostic or surgical procedure and the space constraints within the operating room among other factors. If it is necessary to change one or more of the surgery-related devices being used during a procedure, the Assistant (A) may remove the surgery-related device that is no longer needed from the distal end of its slave robotic mechanism, and replace it with another surgery-related device from a tray of such devices in the operating room. Alternatively, a robotic mechanism may be provided for the surgeon to execute tool exchanges using his/her master input device.

Preferably, the master input devices will be movable in the same degrees of freedom as their associated surgery-related devices to provide their respective surgeons with telepresence, or the perception that the master input devices are integral with their associated surgery-related devices, so that their respective surgeons have a strong sense of directly controlling them. To this end, position, force, and tactile feedback sensors are preferably employed that transmit position, force, and tactile sensations from the devices (or their respective slave robotic mechanisms) back to their associated master input devices so that the operating surgeons may feel such with their hands as they operate the master input devices.

To further enhance the telepresence experience, the three-dimensional images displayed on the displays of the master control stations are oriented so that their respective surgeons feel that they are actually looking directly down onto the operating site. To that end, an image of the surgery-related device that is being manipulated by each surgeon appears to be located substantially where the surgeon's hands are located even though the observation points (i.e., the endoscope or viewing camera) may not be from the point of view of the image.

FIG. 4 illustrates, as an example, a block diagram of a master/slave control system 400 for an associated master manipulator and slave manipulator pair. An example of such a master/slave manipulator pair is the master device input 203 of the mentor master control station 101 and the slave robotic mechanism 121. Master manipulator inputs and corresponding slave manipulator outputs are indicated by arrows AB, and slave manipulator inputs and corresponding master manipulator outputs in the case of feedback are indicated by arrows BA.

Although the master processing unit 420 and slave processing unit 430 described herein may be implemented as analog circuitry, preferably they are implemented digitally using conventional Z-transform techniques for sampled data systems and provided in program code executed by processors of master control stations associated with the master and slave manipulators, 404 and 416, as will be described in further detail in reference to FIG. 10.

In the following description, the master manipulator (i.e., master input device) 404 will be referred to as the master and the slave manipulator (i.e., slave robotic mechanism) 416 will be referred to as the slave, to simplify the description. Also, positions sensed by joint encoders in the master manipulator as well as those in the slave manipulator are referred to as “joint space” positions. Furthermore, references to positions and positioned signals may include orientation, location, and/or their associated signals. Similarly, forces and force signals may generally include both force and torque in their associated signals.

For ease of explanation, the master/slave control system 400 will be described from an initial condition in which the master is at an initial position and the slave is at a corresponding initial position. However, in use, the slave tracks the master position in a continuous manner.

Referring to the control system 400, the master is moved from an initial position to a new position corresponding to a desired position of the end effector (located on the distal end of the slave) as viewed by the surgeon on his display. Master control movements are input by the surgeon 402, as indicated by arrow AB1, by applying a force to the master 404 to cause the master 404 to move from its initial position to the new position.

As the master 404 is thus manipulated by the surgeon, signals from the encoders on the master 404 are input to a master controller 406 as indicated by arrow AB2. At the master controller 406, the signals are converted to a joint space position corresponding to the new position of the master. The joint space position is then input to a master kinematics converter 408 as indicated by arrow AB3. The master kinematics converter 408 then transforms the joint space position into an equivalent Cartesian space position. This is optionally performed by a kinematics algorithm including a Jacobian transformation matrix, inverse Jacobian, or the like. The equivalent Cartesian space position is then input to a bilateral controller 410 as indicated by arrow AB4.

Position comparison and force calculation may, in general, be performed using a forward kinematics algorithm which may include a Jacobian matrix. The forward kinematics algorithm generally makes use of a reference location, which is typically selected as the location of the surgeon's eyes. Appropriate calibration or appropriately placed sensors on the master control station can provide this reference information. Additionally, the forward kinematics algorithm will generally make use of information concerning the lengths and angular offsets of the linkage of the master. More specifically, the Cartesian position represents, for example, the distance of the input handle from, and the orientation of the input handle relative to, the location of the surgeon's eyes. Hence, the equivalent Cartesian space position is input into bilateral controller 410 as indicated by AB4.

In a process similar to the calculations described above, the slave position is also generally observed using joint encoders of the slave 416. In an exemplary embodiment, joint encoder signals read from the slave 416 are provided to a slave controller 414, as indicated by BA2, which converts the signals to a joint space position corresponding to the initial position of the slave 416. The joint space position is then input to a slave kinematics converter 412 as indicated by arrow BA3. The slave kinematics converter 412 then transforms the joint space position into an equivalent Cartesian space position.

In this case, the forward kinematics algorithm used by the slave kinematics converter 412 is preferably provided with the referenced location of a tip of a stereoscopic endoscope capturing images of the surgery site to be viewed on the surgeon display. Additionally, through the use of sensors, design specifications, and/or appropriate calibration, this kinematics algorithm incorporates information regarding the lengths, offsets, angles, etc., describing the linkage structure of the slave cart 120, and set-up joints for the slave 416 (i.e., joints used to initially position the slave that are subsequently locked during the procedure) so that the slave Cartesian position transferred to the bilateral controller 410 is measured and/or defined relative to the tip of the stereoscopic endoscope.

At bilateral controller 410, the new position of the master in Cartesian space relative to the surgeon's eyes is compared with the initial position of the tip of the end effector connected at the distal end of the slave 416 in Cartesian space relative to the tip of the stereoscopic endoscope.

Advantageously, the comparison of these relative relationships occurring in the bilateral controller 410 can account for differences in scale between the master input device space in which the master input device 404 is moved as compared with the surgical workspace in which the end effectors on the distal end of the slave robotic mechanism 416 move. Similarly, the comparison may account for possible fixed offsets, should the initial master and slave positions not correspond.

Since the master has moved to a new position, a comparison by the bilateral controller 410 of its corresponding position in Cartesian space with the Cartesian space position of the slave corresponding to its initial position yields a deviation and a new slave position in Cartesian space. This position is then input to the slave kinematics converter 412 as indicated by arrow ABS, which computes the equivalent joint space position commands.

These commands are then input to the slave controller 414 as indicated by arrow AB6. Necessary joint torques are computed by the slave controller 414 to move the slave to its new position. These computations are typically performed using a proportional integral derivative (P.I.D.) type controller. The slave controller 414 then computes equivalent motor currents for these joint torque values, and drives electrical motors on the slave 416 with these currents as indicated by arrow AB7. The slave 416 is then caused to be driven to the new slave position which corresponds to the new master position.

The control steps involved in the master/slave control system 400 as explained above are typically carried out at about 1300 cycles per second or faster. It will be appreciated that although reference is made to an initial position and new position of the master, these positions are typically incremental stages of a master control movement. Thus, the slave is continually tracking incremental new positions of the master.

The master/slave control system 400 also makes provision for force feedback. Thus, should the slave 416 (i.e., its end effector) be subjected to an environmental force at the surgical site, e.g., in the case where the end effector pushes against tissue, or the like, such a force is fed back to the master 404 so that the surgeon may feel it. Accordingly, when the slave 416 is tracking movement of the master 404 as described above and the slave 416 pushes against an object at the surgical site resulting in an equal pushing force against the slave 416, which urges the slave 416 to move to another position, similar steps as described above in the forward or control path take place in the feedback path.

The surgical environment is indicated at 418 in FIG. 4. In the case where an environmental force is applied on the slave 416, such a force causes displacement of the end effector. This displacement is sensed by the encoders on the slave 416 which generate signals that are input to the slave controller 414 as indicated by arrow BA2. The slave controller 414 computes a position in joint space corresponding to the encoder signals, and provides the position to the slave kinematics converter 412, as indicated by arrow BA3.

The slave kinematics converter 412 computes a Cartesian space position corresponding to the joint space position, and provides the Cartesian space position to the bilateral controller 410, as indicated by arrow BA4. The bilateral controller 410 compares the Cartesian space position of the slave with a Cartesian space position of the master to generate a positional deviation in Cartesian space, and computes a force value corresponding to that positional deviation that would be required to move the master 404 into a position in Cartesian space which corresponds with the slave position in Cartesian space. The force value is then provided to the master kinematics converter 408, as indicated by arrow BA5.

The master kinematics converter 408 calculates from the force value received from the bilateral controller 410, corresponding torque values for the joint motors of the master 404. This is typically performed by a Jacobian Transpose function in the master kinematics converter 408. The torque values are then provided to the master controller 406, as indicated by arrow BA6. The master controller 406, then determines master electric motor currents corresponding to the torque values, and drives the electric motors on the master 404 with these currents, as indicated by arrow BA7. The master 404 is thus caused to move to a position corresponding to the slave position.

Although the feedback has been described with respect to a new position to which the master 404 is being driven to track the slave 416, it is to be appreciated that the surgeon is gripping the master 404 so that the master 404 does not necessarily move. The surgeon however feels a force resulting from feedback torques on the master 404 which he counters because he is holding onto the master 404.

In performing collaborative minimally invasive surgical procedures or training in such procedures, it is useful at times for the lead or mentor surgeon to selectively associate certain master input devices with certain slave robotic mechanisms so that different surgeons may control different surgery-related devices in a collaborative effort or so that selected trainees may practice or experience a minimally invasive surgical procedure under the guidance or control of the mentor surgeon. Some examples of such selective master/slave associations are illustrated in FIGS. 5-9, wherein each master depicted therein includes the master manipulator 404 and master processing 420 of FIG. 4 and each slave depicted therein includes the slave manipulator 416 and slave processing 430 of FIG. 4.

In FIG. 5, an exclusive operation master/slave association is shown in which master 501 has exclusive control over slave 502 (and its attached surgery-related device), and master 511 has exclusive control over slave 512 (and its attached surgery-related device). In this configuration, the masters, 501 and 511, may be controlled by the right and left hands of a surgeon while performing a minimally invasive surgical procedure, or they may be controlled by different surgeons in a collaborative minimally invasive surgical procedure. The master/slave control system 400 may be used for each associated master/slave pair so that lines 503 and 513 (master to slave direction) correspond to its forward path AB4 line and lines 504 and 514 (slave to master direction) correspond to its feedback path BA5 line.

In FIG. 6, a unilateral control master/slave association is shown in which master 601 has exclusive control over slave 602 (and its attached surgery-related device), but input and reflected force (or position) values are provided to the master 611 as well as the master 601. In this configuration, although the master 611 cannot control the slave 602, it tracks the master 601 so that a surgeon holding the master input device of master 611 can feel and experience movement of the master input device of master 601 as it is being manipulated by another surgeon. Thus, this sort of configuration may be useful in training surgeons by allowing them to experience the movement of the master input device of the master 601 as it is being manipulated by a mentor surgeon during a minimally invasive surgical procedure, while viewing the surgical site in their respective displays and communicating with the mentor surgeon using their respective headsets.

In FIG. 7, a modified version of the unilateral control master/slave association is shown. In this configuration, not only does the surgeon holding the master input device of master 711 experience the movement of (and forces exerted against) the master input device of the master 701 as it is being manipulated by another surgeon during a minimally invasive surgical procedure, the surgeon associated with master 711 can also “nudge” the master input device of the master 701 by manipulating his/her master input device since a force value corresponding to such nudging is provided back to the master 701, as indicated by the arrow 722. This “nudging” master/slave configuration is useful for training surgeons, because it allows a trainee surgeon to practice by performing the surgical procedure by manipulating the slave 702 (and its attached surgery-related device) using the master input device of his/her master 701, while the mentor surgeon monitors such manipulation by viewing the surgical site on his/her display while feeling the movement of the trainee surgeon's master input device through input and feedback forces, respectively indicated by arrows 721 and 704. If the mentor surgeon thinks that the trainee surgeon should modify his/her operation of his/her master input device, the mentor surgeon can nudge the trainee surgeon's master input device accordingly, while at the same time, communicating such recommendation verbally to the trainee surgeon using a shared audio system through their respective headsets.

In FIG. 8, a unilateral, shared master/slave association, which is a variant of the nudging configuration of FIG. 7, is shown in which either (or both) masters 801 and 811 may control slave 802. In this configuration, not only does the surgeon holding the master input device of master 811 experience the movement of (and forces exerted against) the master input device of the master 801 as it is being manipulated by another surgeon during a minimally invasive surgical procedure, the surgeon associated with master 811 can also control the slave 802 if desired, as indicated by the arrow 813. This “override” master/slave configuration is useful for training surgeons, because it allows a trainee surgeon to practice by performing the surgical procedure by manipulating the slave 802 (and its attached surgery-related device) using the master input device of his/her master 801, while the mentor surgeon monitors such manipulation by viewing the surgical site on his/her display while feeling the movement of the trainee surgeon's master input device through input and feedback forces, respectively indicated by arrows 821 and 804. If the mentor surgeon finds it necessary to assume control of the slave 802 to avoid injury to a patient, the mentor surgeon can assert such control accordingly, while at the same time, communicating that he/she is taking over control verbally to the trainee surgeon through a shared audio system.

In FIG. 9, a bilateral master/slave association is shown in which masters, 901 and 912, and slaves, 902 and 912, all move in tandem, tracking each other's movements. In this configuration, the slave 912 (and its attached surgery-related device) may be controlled by a surgeon using the master 901, while another surgeon experiences its movement by loosely holding the master input device for the other master 911. The slave 902 in this case is generally non-operative in the sense that it is not directly participating in the minimally invasive surgical procedure. In particular, the slave 902 either may not have the distal end of its slave robotic mechanism inserted in the patient so that its robotic arm moves, but does not result in any action taking place in the surgical site, or the slave 902 may only include a computer model of the linkages, joints, and joint motors of its slave robotic mechanism, rather than the actual slave robotic mechanism.

However, the slave 902 does move in tandem with the slave 912 (in actuality or through simulation) as the surgeon manipulating the master input device of the master 901 causes the slave 912 to move, because a force (or position) value corresponding to such manipulation is provided to the master 911, as indicated by arrow 921, and the master 911 controls the slave 902 to move accordingly, as indicated by arrow 913. Any forces asserted against the surgery-related device attached to the distal end of the slave robotic mechanism of the slave 912 are then fed back to the master input device of the master 911, as indicated by the arrow 914.

Note that the surgeon associated with the master 911 can effectively “nudge” the master 901 by manipulating the master input device of the master 911. Therefore, the bilateral master/slave association shown in FIG. 9 can also be used in the training of surgeons in a similar manner as the “nudging” and unilateral, shared master/slave associations respectively shown in FIGS. 7 and 8.

FIG. 10 illustrates a block diagram of components of the multi-user medical robotic system for selective association of master manipulators (also referred to as “master input devices”), 404 and 1004, with slave manipulators (also referred to as “slave robotic mechanisms”), 416 and 1016. Although only two master manipulators and two slave manipulators are shown in this example, it is to be appreciated that any number of master manipulators may be associated with any number of slave manipulators in the system, limited only by master control station port availability, memory capacity, and processing capability/requirements.

The master processing unit 420 includes the master controller 406 and the master kinematics converter 408 and generally operates as described in reference to FIG. 4, and the master processing unit 1020 is similarly configured and functionally equivalent to the master processing unit 420. The slave processing unit 430 includes the slave controller 414, slave kinematics converter 412, and the bilateral controller 410 and generally operates as described in reference to FIG. 4, and the slave processing unit 1030 is similarly configured and functionally equivalent to the slave processing unit 430.

An association module 1001 includes a shared command filter 1002 and a routing table 1003 for selectively associating master manipulators, 404 and 1004, with slave manipulators, 416 and 1016. In brief, the routing table 1003 indicates which inputs are routed to which outputs of the association module 1001, and the shared command filter 1002 determines how shared command of a slave manipulator by two master manipulators is handled. One or more switch commands 1005 are provided to the association module 1001 as a means for a user to alter parameters of the shared command filter 1002 or values in the routing table 1003 so as to change or switch the selected associations between master and slave manipulators. The current parameters of the shared command filter 1002 and/or values in the routing table 1003 may be indicated to the user using a plurality of icons on a graphical user interface of an auxiliary display or the user's master control station display, or they may be indicated by a plurality of light-emitting-diodes or other such indicators on or adjacent to the user's master control station, or they may be indicated by any other display mechanism.

The switch command(s) 1005 may be generated by any one or combination of: the user interacting with one or more buttons on the master input devices, the user interacting with one or more foot pedals associated with the user's master control station, the user providing recognizable voice commands to a voice recognition (i.e., word recognition) and processing system, the user interacting with one or more menus displayed on the user's master control station display, or the user interacting with any other conventional input mechanism of such sort.

In a preferred embodiment compatible with the multi-user medical robotic system of FIG. 1, master processing 420 is performed as executable program code on a processor associated with the master control station of the master manipulator 404, and master processing 1020 is also performed as executable program code on a processor associated with the master control station of the master manipulator 1004. Both master control stations in this case may be Trainee master control stations, such as master control stations 131 and 161 of FIG. 1, or one of the master control stations may be the Mentor master control station 101 and the other, a Trainee master control station.

The slave processing 430, the slave processing 1030, and the association module 1001 are preferably included as executable program or table code on the processor 220 associated with the Mentor master control station 101. The switch command(s) 1005 in this case originate from action taken by the Mentor Surgeon (M) operating the Mentor master control station 101.

The Mentor master control station 101 preferably performs the slave processing for all slave robotic mechanisms 121-123, because it communicates directly with the slave robotic mechanisms 121-123, whereas the Trainee master control stations only communicate indirectly with the slave robotic mechanisms 121-123 through the Mentor master control station 101. On the other hand, the Trainee master control stations preferably perform the master processing for their respective master input devices, so that such processing may be performed in parallel with the slave processing (while maintaining time synchronization) while off-loading these processing requirements from the processor of the Mentor master control station 101. Thus, this distribution of processing makes efficient use of processor resources and minimizes processing delay.

One feature of the present invention is the capability to selectively associate on-the-fly both command and feedback paths between the master and slave manipulators. For example, the exclusive operation master/slave association shown in FIG. 5 may be altered on-the-fly (i.e., during a minimally invasive surgical procedure rather than at set-up) to the bilateral master/slave association shown in FIG. 9 by re-associating the command path of the master 501 from the slave 502 to the slave 512 while maintaining the feedback path of the slave 502 to the master 501, re-associating the command path of the master 511 from the slave 512 to the slave 502 while maintaining the feedback path of the slave 512 to the master 511, providing a value indicating the input force applied against the master 501 to the master 511, and providing a value indicating the input force applied against the master 511 to the master 501.

FIG. 11 illustrates an example of input/output ports for the association module 1001, in which input ports A-F are shown on the left side of the association module 1001 for convenience, and output ports U-Z are shown on the right side of the association module 1001 for convenience.

Input port A is assigned to the output of the master processing 420 which is provided on line 1014 of FIG. 10, input port B is assigned to the surgeon force input to the master manipulator 404 which is provided on line 1042 of FIG. 10, input port C is assigned to surgeon force input to the master manipulator 1004 which is provided on line 1052 of FIG. 10, input port D is assigned to the output of the master processing 1020 which is provided on line 1054 of FIG. 10, input port E is assigned to the output of the slave processing 430 which is provided on line 1035 of FIG. 10, and input port F is assigned to output of the slave processing 1030 which is provided on line 1075 of FIG. 10.

Output port U is assigned to the input to the slave processing 430 which is provided on line 1024 of FIG. 10, output port V is assigned to the input force to the master manipulator 1004 which is provided on line 1053 of FIG. 10, output port W is assigned to the input force to the master manipulator 404 which is provided on line 1042 of FIG. 10, output port X is assigned to the input to the slave processing 1030 which is provided on line 1064 of FIG. 10, output port Y is assigned to the feedback to the master processing 420 which is provided on line 1045 of FIG. 10, and output port Z is assigned to the feedback to the master processing 1020 which is provided on line 1085 of FIG. 10.

FIG. 12 illustrates a routing table corresponding to the master/slave association shown in FIG. 9, and FIG. 13 illustrates a routing table corresponding to the master/slave association shown in FIG. 8. Referring to FIG. 12, input port A is connected to output port X (i.e., line 1014 is coupled to line 1064 of FIG. 10, which corresponds to line 903 of FIG. 9), input port B is coupled to output port V (i.e., line 1042 is coupled to line 1053 of FIG. 10, which corresponds to line 921 of FIG. 9), input port C is connected to output port W (i.e., line 1052 is coupled to line 1043 of FIG. 10, which corresponds to line 922 in FIG. 9), input port D is connected to output port U (i.e., line 1054 is coupled to line 1024 of FIG. 10, which corresponds to line 913 in FIG. 9), input port E is connected to output port Y (i.e., line 1035 is coupled to line 1045 of FIG. 10, which corresponds to line 904 in FIG. 9), and input port F is connected to output port Z (i.e., line 1075 is coupled to line 1083 of FIG. 10, which corresponds to line 914 in FIG. 9).

If the Mentor Surgeon (M) is operating the master 901 and desires at this point to change the master/slave association from that of FIG. 9 to that of FIG. 8, he/she provides appropriate switch command(s) 1005 by, for example, depressing a button on his/her right-hand master input device corresponding to the master 901 so that the command output of the master 901 is provided to the slave 902 instead of the slave 912, and selecting menu entries on his/her display to stop providing commands to or receiving force feedback from the slave 912, to provide the force feedback from the slave 902 to the master 911 (as well as continuing to do so to the master 901), and stop providing the input force exerted on the master input device of the master 911 to the master 901. Alternatively, as previously described, these switches may be done using foot pedals, voice actuation, or any combination of buttons, foot pedals, voice, display menu, or other actuation devices controllable by the Mentor Surgeon (M).

FIG. 13 illustrates the routing table resulting from the above described switch command(s) 1005 that places the master/slave association into the configuration shown in FIG. 8. In this case, input port A is connected to output port U (i.e., line 1014 is coupled to line 1024 of FIG. 10, which corresponds to line 803 of FIG. 8), input port B is coupled to output port V (i.e., line 1042 is coupled to line 1053 of FIG. 10, which corresponds to line 821 of FIG. 8), input port C is not connected to any output port, input port D is connected to output port U (i.e., line 1054 is coupled to line 1024 of FIG. 10, which corresponds to line 813 in FIG. 8), input port E is connected to output ports Y and Z (i.e., line 1035 is coupled to line 1045 and 1085 of FIG. 10, which corresponds to line 804 in FIG. 8), and input port F is not connected to any output port.

Referring back to FIG. 8 now, it is noted that the slave 802 has two command inputs, one from the master 801 and another from the master 811. This causes a control contention issue which may be resolved by the shared command filter 1002 of the association module 1001 of FIG. 10.

FIGS. 14 and 15 illustrate block diagrams for alternative embodiments of the shared command filter 1002. As shown in FIG. 14, the shared command filter 1002 takes the form of a simple arbiter, selecting either a first command input CMD1 or a second command input CMD2, depending upon a priority input which is provided as a switch command 1005 to the association module 1001 by the Mentor Surgeon (M) or programmed into or provided as a parameter value for its process code. As shown in FIG. 15, the shared command filter 1002 may also take the form of a weighter or weighting function that weights command inputs CMD1 and CMD2, and combines the weighted values to determine a shared command value to be provided to the slave. In this case, the respective weights of the first and second command inputs, CMD1 and CMD2, depend on a weight input which is provided as a switch command 1005 to the association module 1001 by the Mentor Surgeon (M), or programmed into or provided as parameter values for its process code.

In the foregoing description of the switching process from one master/slave association to another, it has been assumed that such switching occurs instantaneously. However, to avoid undesirable transient movement of the slave robotic mechanisms, it may be desirable in certain circumstances to phase-in the switching process (i.e., gradually reducing the strength of the signal being switched out while gradually increasing the strength of the signal being switched in), or using a clutch mechanism that disengages both signals and only engages the new signal, for example, after making sure that the position of the slave robotic mechanism being commanded by the new signal matches that of the old signal so that a sudden movement will not occur as a result of the change.

Alternative telesurgical networks are schematically illustrated in FIGS. 16 and 17. An operator O and an Assistant 43 may cooperate to perform an operation by passing control of instruments between input devices, and/or by each manipulating their own instrument or instruments during at least a portion of the surgical procedure. Referring, now to FIG. 16, during at least a portion of a surgical procedure, for example, cart 305 is controlled by Operator O and supports an endoscope and two surgical instruments. Simultaneously, for example, cart 308 might have a stabilizer and two other surgical instruments, or an instrument and another endoscope. The surgeon or operator O and assistant 43 cooperate to perform a stabilized heating heart coronary artery bypass grafting (CABG) procedure by, for example, passing a needle or other object back and forth between the surgical instruments of carts 305, 308 during suturing, or by having the instruments of cart 308 holding the tissue of the two vessels being anastomosed while the two instruments of cart 305 are used to perform the actual suturing. Such cooperation heretofore has been difficult because of the volumetric space required for human hands to operate. Since robotic surgical end effectors require much less space in which to operate, such intimate cooperation during a delicate surgical procedure in a confined surgical space is now possible. Optionally, control of the tools may be transferred or shared during an alternative portion of the procedure.

Referring now to both FIGS. 16 and 17, cooperation between systems is also possible. The choice of how many masters and how many corresponding slaves to enable on a cooperating surgical system is somewhat arbitrary. Within the scope of the present invention, one may construct a single telesurgical system's architecture to handle five or six manipulators (e.g., two masters and three or four slaves) or ten or twelve manipulators (e.g., four masters and six or eight manipulators), although any number is possible. For a system having multiple master controls, the system may be arranged so that two operators can operate the same surgical system at the same time by controlling different slave manipulators and swapping manipulators as previously described.

Alternatively, it may be desirable to have a somewhat modular telesurgical system that is capable both of conducting one particular surgical operation with only one operator and, for example, five or six manipulators, and which is also capable of coupling to another modular system having five or six manipulators to perform a second surgical procedure in cooperation with a second operator driving the second system. For such modular systems, five or six manipulator arms are preferably supported by the architecture, although any number may be incorporated into each system. One advantage of the modular system over a single, larger system is that when decoupled, the modular systems may be used for two separate simultaneous operations at two different locations, such as in adjacent operating rooms, whereas such might be quite difficult with a single complex telesurgical system.

As can be understood with reference to FIG. 16, a simple manner of having two surgical systems, each having an operator, to cooperate during a surgical procedure is to have a single image capture device, such as an endoscope, produce the image for both operators. The image can be shared with both displays by using a simple image splitter. If immersive display is desired, the two systems might additionally share a common point of reference, such as the distal tip of the endoscope, from which to calculate all positional movements of the slave manipulators. With the exception of the imaging system, each control station might be independent of the other, and might be operatively coupled independently to its associated tissue manipulation tools. Under such a simple cooperative arrangement, no swapping of slave manipulators from one system to another would be provided, and each operator would have control over only the particular slave manipulators attached directly to his system. However, the two operators would be able to pass certain objects back and forth between manipulators, such as a needle during an anastomosis procedure. Such cooperation may increase the speed of such procedures once the operators establish a rhythm of cooperation. Such an arrangement scenario may, for example, be used to conduct a typical CABG procedure, such that one operator would control the endoscope and two tissue manipulators, and the other operator would control two or three manipulators to aid in harvesting the internal mammary artery (IMA) and suturing the arterial blood source to the blocked artery downstream of the particular blocked artery in question. Another example where this might be useful would be during beating heart surgery, such that the second operator could control a stabilizer tool in addition to two other manipulators and could control the stabilizer while the first operate performed an anastomosis.

One complication of simple cooperative arrangements is that if the first operator desired to move the image capture device, the movement might alter the image of the surgical field sufficiently that the second operator would no longer be able to view his slave manipulators. Thus, some cooperation between the operators, such as audible communications, might be employed before such a maneuver.

A slightly more complicated arrangement of surgical manipulators on two systems within the scope of the present invention, occurs when operators are provided with the ability to “swap” control of manipulator arms. For example, the first operator is able to procure control over a manipulator arm that is directly connected to the second operator's system. Such an arrangement is depicted in FIG. 16.

With the ability to operatively hook multiple telesurgical systems together, an arrangement akin to a surgical production line can be envisioned. For example, a preferred embodiment of the present invention is shown in FIG. 17. Therein, a single master surgeon O occupies a central master control operating room. Satellite operating rooms (ORs) 952, 954 and 956 are each operatively connected to the central master console via switching assembly 958, which is selectively controlled by Operator O. While operating on a first patient P1 in OR 956, the patients in ORs 954 and 952 are being prepared by assistants A2 and A3, respectively. During the procedure on patient P1, patient P3 becomes fully prepared for surgery, and A3 begins the surgery on the master control console dedicated to OR 952 by controlling manipulator assembly 964. After concluding the operation in OR 956, Operator O checks with Assistant 43 by inquiring over an audio communications network between the ORs whether Assistant 43 requires assistance. OR 950 might additionally have a bank of video monitors showing the level of activity in each of the ORs, thereby permitting the master surgeon to determine when it would be best to begin to participate in the various ongoing surgeries, or to hand control off to others to continue or complete some of the surgeries.

Returning to the example, if Assistant 43 requests assistance, O selects OR 952 via switching assembly 958, selects a cooperative surgery set-up on an OR-dedicated switching assembly 960, and begins to control manipulator assembly 962. After completion of the most difficult part of the surgery in OR 952, O switches over to OR 954, where patient P2 is now ready for surgery.

The preceding description is a mere example of the possibilities offered by the cooperative coupling of masters and slaves and various telesurgical systems and networks. Other arrangements will be apparent to one of skill in the art reading this disclosure. For example, multiple master control rooms can be imagined in which several master surgeons pass various patients back and forth depending on the particular part of a procedure being performed. The advantages of performing surgery in this manner are myriad. For example, the master surgeon O does not have to scrub in and out of every procedure. Further, the master surgeon may become extremely specialized in performing part of a surgical procedure, e.g., harvesting an IMA, by performing just that part of a procedure over and over on many more patients than he otherwise would be able to treat. Thus, particular surgical procedures having distinct portions might be performed much more quickly by having multiple surgeons, with each surgeon each performing one part of the procedure and then moving onto another procedure, without scrubbing between procedures. Moreover, if one or more patients (for whatever reason) would benefit by having a surgeon actually be present, an alternative surgeon (different from the master surgeon) may be on call to one or more operating rooms, ready to jump in and address the patient's needs in person, while the master surgeon moves on treat another patient. Due to increased specialization, further advances in the quality of medical care may be achieved.

In addition to enabling cooperative surgery between two or more surgeons, operatively hooking two or more operator control stations together in a telesurgical networking system also may be useful for surgical training. A first useful feature for training students or surgeons how to perform surgical procedures would take advantage of a “playback” system for the student to learn from a previous operation. For example, while performing a surgical procedure of interest, a surgeon would record all of the video information and all of the data concerning manipulation of the master controls on a tangible machine readable media. Appropriate recording media are known in the art, and include videocassette or Digital Video Disk (DVD) for the video images and/or control data, and Compact Disk (CD), e.g., for the servo data representing the various movements of the master controls.

if two separate media are used to record the images and the servo data, then some method of synchronizing the two would be desirable during feedback, to ensure that the master control movements substantially mirror the movements of the slave manipulators in the video image. A crude but workable method of synchronization might include a simple time stamp and a watch. Preferably, both video images and servo data would be recorded simultaneously on the same recording medium, so that playback would be automatically synchronized.

During playback of the operation, a student could place his hands on the master controls and “experience” the surgery, without actually performing any surgical manipulations, by having his hands guided by the master controls through the motions of the slave manipulators shown on the video display. Such playback might be useful, for example, in teaching a student repetitive motions, such as during suturing. In such a situation, the student would experience over and over how the masters might be moved to move the slaves in such a way as to tie sutures, and thus hopefully would learn how better to drive the telesurgical system before having to perform an operation.

The principles behind this playback feature can be built upon by using a live hand of a second operator instead of simple data playback. For example, two master control consoles may be connected together in such a way that both masters are assigned to a single set of surgical instruments. The master controls at the subordinate console would follow or map the movements of the masters at the primary console, but would preferably have no ability to control any of the instruments or to influence he masters at the primary console. Thus, the student seated at the subordinate console again could “experience” a live surgery by viewing the same image as the surgeon and experiencing how the master controls are moved to achieve desired manipulation of the slaves.

An advanced version of this training configuration includes operatively coupling two master consoles into the same set of surgical instruments. Whereas in the simpler version, one console was subordinate to the other at all times, this advanced version permits both master controls to control motion of the manipulators, although only one could control movement at any one time. For example, if the student were learning to drive the system during a real surgical procedure, the instructor at the second console could view the surgery and follow the master movements in a subordinate role. However, if the instructor desired to wrest control from the student, e.g., when the instructor detected that the student was about to make a mistake, the instructor would be able to override the student operator by taking control over the surgical manipulators being controlled by the student operator. The ability to so interact would be useful for a surgeon supervising a student or second surgeon learning a particular operation. Since the masters on the instructor's console were following the surgery as if he were performing it, wresting control is a simple matter of clutching into the surgery and overriding the control information from the student console. Once the instructor surgeon had addressed the issue, either by showing the student how to perform a certain part of the surgical procedure or by performing it himself, the instructor could clutch out of the operation and permit the student to continue.

An alternative to this “on-off” clutching whereby the instructor surgeon is either subordinate to the student or in command would be a variable clutch arrangement. For example, again the instructor is subordinate to the student's performance of a procedure, and has his masters follow the movement of the student's master controls. When the instructor desires to participate in the procedure, but does not desire to wrest all control from the student, the instructor could begin to exert some control over the procedure by partially clutching and guiding the student through a certain step. If the partial control was insufficient to achieve the instructor's desired result, the instructor could then completely clutch in and demonstrate the desired move, as above. Variable clutching could be achieved by adjusting an input device, such as a dial or a foot pedal having a number of discrete settings corresponding to the percentage of control desired by the instructor. When the instructor desires some control, he or she could operate the input device to achieve a setting of, for example, 50 percent control, in order to begin to guide the student's movements. Software could be used to calculate the movements of the end effectors based on the desired proportionate influence of the instructor's movements over the student's. In the case of 50% control, for example, the software would average the movements of the two sets of master controls and then move the end effectors accordingly, producing resistance to the student's desired movement, thereby causing the student to realize his error. As the surgeon desires more control, he or she could ratchet the input device to a higher percentage of control, finally taking complete control as desired.

Other examples of hooking multiple telesurgical control stations together for training purposes will be apparent to one of skill in the art upon reading this disclosure. Although these training scenarios are described by referring to real surgery, either recorded or live, the same scenarios could be performed in a virtual surgical environment, in which, instead of manipulating the tissue of a patient (human or animal) cadaver, or model, the slave manipulators could be immersed, in a virtual sense, in simulation software. The software would then create a simulated virtual surgical operation in which the instructor and/or student could practice without the need for a live patient or an expensive model or cadaver.

Although the various aspects of the present invention have been described with respect to a preferred embodiment, it will be understood that the invention is entitled to full protection within the full scope of the appended claims. 

1. A robot system, comprising: a robot that has a camera and a monitor; a first remote station that has a monitor and is configured to access and control said robot, said first remote station having a first input device operated by a first user to cause movement of said robot; a second remote station that has a monitor and is configured to access and control said robot, said second remote station having a second input device operated by a second user to cause movement of said robot; and, an arbitrator that can operate in an exclusive mode to control access and control movement of said robot exclusively by said first remote station or second remote station, said arbitrator provides a mechanism that allows said first remote station to exclusively access and control movement of said robot, said mechanism denies exclusive access to said robot by said second remote station.
 2. A robot system, comprising: a first robot and a second robot that each have a camera that can generate an image, a monitor, a speaker and a microphone that can generate audio; a first remote station that can access said first and second robots, said first remote station including a camera, a monitor that can receive said image from said first or second robots, a microphone and a speaker that can produce audio provided by said first or second robots; a second remote station that can access said first and second robots, said second remote station including a camera, a monitor that can receives said image from said first and second robots, a microphone and a speaker that can produce audio provided by said first and second robots; and a server coupled to said first and second robots and said first and second remote stations, said server allows exclusive access to said first robot by said first remote station such that said image and audio from said first robot is provided to said first remote station and said image and audio are not provided to said second remote station and even though said second remote station is prevented from accessing said first robot said server allows said second remote station to access said second robot. 